function findSlide(hash) {
          var target = null;
          var slides = GetElementsWithClassName('*','slide');
          for (var i = 0; i < slides.length; i++) {
                  var targetSlide = slides[i];
                  if ( (targetSlide.name && targetSlide.name == hash)
                   || (targetSlide.id && targetSlide.id == hash) ) {
                          target = targetSlide;
                          break;
                  }
          }
          while(target != null && target.nodeName != 'BODY') {
                  if (hasClass(target, 'slide')) {
                          return parseInt(target.id.slice(5));
                  }
                  target = target.parentNode;
          }
          return null;
  }